Product scope
REX615 is ABB’s modular protection and control relay platform for distribution and generation applications. ABB lists feeder, line differential, transformer, machine, shunt capacitor, interconnection, voltage, busbar and arc-protection uses.
Architecture
The manufacturer describes scalable hardware and software, integrated arc-flash protection and IEC 61850 support. Multiple application packages do not mean every function is present in every ordered relay.
Engineering interpretation
A common platform can reduce engineering diversity, but standardisation must include exact application package, analog-input type, I/O, communication board, firmware, settings template and cybersecurity baseline.
Specification caution
Verify the order code and intended function set. Do not use a family-level feature list as proof that the delivered relay includes a particular protection element, sensor input or redundant Ethernet option.
Official sources and revision control
Technical review date: 16 August 2026. Standards and product capabilities can change; confirm the project-specific edition, firmware, options and ordered configuration before engineering or procurement.